Insulator structure



April 8, 1941. B. STEWART Erm.

INSULATOR STRUCTURE 3, C. www, mi

Lo RY BST-Wma? AND ALVIN J. ,STEWART Their Patented Apr. y8, 1941 UNITED STATES PATENT OFFICE ENSULATOR STRUCTURE Application December 3, 1938, Serial No. 243,840

4 Claims.

This invention relates to an insulator structure particularly adap-ted for use as a three way bracket for telephone, telegraph or forv central station of for any wires conveying electrical energy, to be used mainly on telephone poles, although capable of more general use on buildings or other supports.

It is further aimed to provide an insulator structure of the general character mentioned which may be molded with an emcient reinforcement therein which coacts terminally with the pole or other support to prevent turning of the insulator structure `and which further coacts with a fastening or securing element.

Another object is to provide an insulator structure wherein torsional strain on the insulator and fastening is minimized.

A further object is to provide such an insulator having spools provided with outwardly extending tapered or equivalent portions to better accommodate angularly disposed wire leads.

Various additional objects and advantages will become apparent from a consideration of the description following taken in connection with accompanying drawing illustrating an operative embodiment.

T11 said drawing:

Fig. 1 is a View in side elevation showing an improved insulator bracket in connection with a lag screw;

Fig. 2 is a plan view of the insulator bracket;

Fig. 3 is an end elevation of the insulator bracket;

Fig. 4 is a cross section taken of Fig. 1;

Fig. 5 is a cross section taken on the line 5 5 of Fig. 1;

Fig. 6 is a longitudinal central section showing the insulator bracket attached to a pole by a bolt;

Fig. '7 is a detail perspective View of the metallic or reinforcing frame;

Fig. 8 is a detail perspective view of a modiiied form of metallic or reinforcing frame;

Fig. 9 is a front elevation of a modilied form of insulator bracket, and

Fig. 10 is detail perspective of the form of metallic or reinforcing frame used in the form of Fig. 9.

Referring specically to the drawing wherein like reference characters designate like or similar parts throughout the dilferent views, Io designates an insulator bracket which is usually generally of U-shape and comprising a metallic reinforcing frame and a body II of suitable insuon the line 5 4 lation molded thereon while in a plastic state, and for instance, glass, porcelain, and synthetic resin. This structure provides parallel, spaced apart legs or side spools I2 having any desired number of wire or lead-engaging grooves I3. In line with such spools I2 are heads o1' relatively fiat portions Ill adapted to receive hammer blows and from which spools I5 extend inwardly, having any desired number of wire or lead-engaging grooves I6. Such spools I5 are joined by a centra] enlargement having upper and lower bosses Il and I8. Ribs or lugs are provided at I9 at the sides of heads l and lugs 20 are provided at the tops thereof, to aid in maintaining the wires or leads which are attached thereto, in proper separated relation. The portions I4, spools I5 and the central enlargement constitute a bridge connecting the legs I2.

Reverting to the metallic reinforcing frame within the body II, and which is generally indicated at A, it may be of the specific form of Fig. '7, that is be made in similar U-shaped sections 2i placed in contact and welded together, the sections being bulged at 22 to collectively provide an eyelet 23, and a terminal at each side of the frame having a pole-entering spur 24 which projects outwardly beyond the spools I2. Such spurs are preferably tapered and have enlargements or blisters 24a thereon to increase the effectiveness of their engagement in the pole or other support. Said frame A has lugs I4a extending upwardly and terminating iiush with surface I4 to receive hammer blows.

In attaching the insulator bracket, the spurs are forced into the pole or other support and, if necessary, blows may be dealt the heads I4 and Il#L to drive the spurs into place. These spurs minimize turning and reduce torsion. In addition, a fastening as at 25 is passed through the bore of the bosses Il and I8 and the eyelet 23. The fastening 25.in Fig. 1 is specifically shown as a lag screw, adapted to engage the same pole or other support as the spurs 24. Obviously any other suitable fastening may be substituted for the lag screw 25.

The legs or side members i2 at inner corners or edges of their attaching ends may be bevelled or otherwise out to better fit a pole when the bracket is installed horizontally.

The different spools I2 and i5 taper or are reduced in an outward direction as shown to better accommodate angular leads or wir-es.

A spool 26 of insulation like the body Il loose- I ly surrounds the fastening 25 and is suiiciently short as not to be clamped against turning when the bracket structure is fastened in place.

As a result, the insulator bracket will accommodate the leads or Wires in eflicient relation, the same being fastened to the grooves of the spools l2 and It with the loose sleeve or spool 26 minimizing torsion or tendencies to turn imparted by Wires in Contact therewith. Should the insulation fracture, there Will still be Ithe interengaged frame A and fastening 25 to prevent detachment of the leads or Wires.

Various changes may be resorted to provided they fall Within the spirit and scope of the invention. For instance in Fig. 6, the insulator bracket structure utilizes a fastening or securing member 2 in the form of a detachable bolt, in lieu. of the lag screw 25.

In Fig. S, a modified form of reinforcing or metallic frame is shown Which may be used in place of that at A, in this instance consisting of a metallic rod bent to provide an eyelet 28 to function like that at 23 and having the free ends of its legs provided with spurs 29 to function like those at 2d, and the upper ends provided With hammer heads 26a to function like those at Mia.

In the further modified form of Figs. 9 and l0, a body Ila of insulation like that at A, is shaped like the body A with the addition of a cross piece Si). Any suitable fastening like that at 25 ory 21 secures the structure in place, passing through eyelets Sl and 32 in a metallic or reinforcing frame 33 and a spool 26a like that at 26. Embedded in the cross piece Si) abutting frame 33 are metallic pins 3d having spurs Sii2L thereon like those at 2d.

We claim as our invention;

1. An insulator structure comprising a rigid body of insulation generally of U-shape providing Aspaced legs adapted at their free ends to contact by the free ends of the legs, said insulator legs being in the form of spools arranged to be su:- rounded by Wire terminals, said spools being reduced in dimension in outward direction to accommodate angularly disposed leads.

2. An insulator structure comprising a rigid body of insulation including substantially parallel side spools, one end of each side spool being free, heads at the other ends of said spools, lugs on said heads to aid in maintaining Wires separated, said free ends being disposed to aibut a support, spools intermediate said heads, boss means joining the second mentioned spools having a bore, and a fastening disposed in said bore extending beyond the free ends of the side spools for attachment to the support.

3. An insulator structure according to claim v2 having a metallic reinforcing frame embedded t therein extending substantially throughout the side spools and across the boss means, said frame having an eyelet registering With said bore and thro-ugh which the fastening passes, and the terminal-s of the frame extending beyond the free ends of the side spools to prevent turning of the insulator structure on the fastening. y Y

4. An. insulator structure comprising a rigid body of insulation'having a portion generally of U-shape providing spaced legs in the form of spools arranged to be surrounded by Wire terminals and providing a bridge connecting adjacent ends of the legs, a metallic frame embedded within the body, said bridge and frame having openings extending completely therethrough located between and approximately parallel to the legs, a fastening member passing through said open ings having its free end at the side of the bridge opposite to the legs and its attaching end located beyonld the other ends of the legs, a spool on the fastening member between said attaching end vand bridge, and means extending from the frame and beyond the other ends of the legs to engage a support to prevent turning of the structure about said fastening member.

LORY B. STEWART. ALVIN J. STEWART. 

